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EUROPEAN AND MEDITERRANEAN PLANT PROTECTION ORGANIZATION
ORGANISATION EUROPEENNE ET MEDITERRANEENNE POUR LA PROTECTION
DES PLANTES
17-23152
Pest Risk Analysis for Cinnamomum camphora
2017
EPPO 21 Boulevard Richard Lenoir
75011 Paris www.eppo.int [email protected]
This pest risk analysis scheme has been specifically amended from the EPPO Decision-Support
Scheme for an Express Pest Risk Analysis document PM 5/5(1) to incorporate the minimum
requirements for risk assessment when considering invasive alien plant species under the EU
Regulation 1143/2014. Amendments and use are specific to the LIFE Project (LIFE15 PRE FR
001) ‘Mitigating the threat of invasive alien plants to the EU through pest risk analysis to
support the Regulation 1143/2014’.
Cite this document as: EPPO (2017) Pest risk analysis for Cinnamomum camphora. EPPO, Paris. Available at: Photo: Cinnamomum camphora (Forest and Kim Starr, Starr Environmental, Bugwood.org)
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EUROPEAN AND MEDITERRANEAN PLANT PROTECTION ORGANIZATION
Pest risk analysis for Cinnamomum camphora (L.) J. Presl
This PRA follows EPPO Standard PM5/5 Decision support scheme for an Express Pest Risk
Analysis
PRA area: EPPO region
First draft prepared by: S. Luke Flory,
Location and date: Paris (FR), 2016-10-17/21
Composition of the Expert Working Group
BRUNDU Giuseppe (Mr) University of Sassari, Department of Agriculture, Viale Italia 39, 07100
Sassari, Italy, [email protected]
CHAPMAN Daniel (Mr) Centre for Ecology and Hydrology, Bush Estate, Eh26 0QB Penicuik, United Kingdom, [email protected]
FLORY S. Luke (Mr) Agronomy Department, University of Florida, 706 SW 21st Ave, FL 32601 Gainsville, United States, [email protected]
LE ROUX Johannes (Mr) Department of Botany and Zoology, Stellenbosh University, Stellenbosch University Private Bag X1, 7602 Matieland, South Africa, [email protected]
PESCOTT Oliver (Mr) Maclean Building, Benson Lane, OX10 8BB Wallingford, Oxfordshire, United Kingdom, [email protected]
SCHOENENBERGER Nicola (Mr)
Natural scientist, INNOVABRIDGE Foundation, Contrada al Lago 19, 6987 Caslano, Switzerland, [email protected]
STARFINGER Uwe (Mr) Julius Kühn Institut (JKI), Federal Research Centre for Cultivated Plants, Institute for National and International Plant Health, Messeweg 11/12, 38104 Braunschweig, Germany, [email protected]
TANNER Rob (Mr) OEPP/EPPO, 21 boulevard Richard Lenoir, 75011 Paris, France, [email protected]
3
The pest risk analysis for Cinnamomum camphora has been
performed under the LIFE funded project:
LIFE15 PRE FR 001
Mitigating the threat of invasive alien plants to the EU through pest
risk analysis to support the Regulation 1143/2014
In partnership with
EUROPEAN AND MEDITERRANEAN PLANT PROTECTION ORGANIZATION
And
NERC CENTRE FOR ECOLOGY AND HYDROLOGY
4
Review Process
• This PRA on Cinnamomum camphora was first drafted by S. Luke Flory
• The PRA was evaluated under an Expert Working Group (EWG) at the EPPO
headquarters between 2016-10-17/21
• Following the finalisation of the document by the Expert Working Group the PRA
was peer reviewed by the following:
(1) The EPPO Panel on Invasive Alien Plants (November and December 2016)
(2) The EPPO PRA Core members (December and January2016/17)
5
Contents
Summary 6
Stage 1: Initiation 9
Stage 2: Pest Risk Assessment 10
1. Taxonomy 10
2. Pest Overview 11
3. Is the pest a vector? 13
4. Is a vector needed for pest entry or spread? 14
5. Regulatory status of the pest 14
6. Distribution 15
7. Habitats and their distribution in the PRA area 17
8. Pathways for entry 18
9. Likelihood of establishment in the natural environment (PRA area) 19
10. Likelihood of establishment in the managed environment (PRA area) 19
11. Spread in the PRA area 20
12. Impact in the current area of distribution 21
12.01. Impact on biodiversity and ecosystem patterns 21
12.02. Impact on ecosystem services 23
12.03. Socio-economic impact 24
13. Potential impact in the PRA area 24
14. Identification of the endangered area 25
15. Climate change 26
16. Overall assessment of risk 28
Stage 3: Pest risk management 30
17. Phytosanitary measures 30
17.01Management measures for eradication, containment and control 30
18. Uncertainty 31
19. Remarks 31
20. References 32
Appendices
Appendix 1 Projection of climate suitability for Cinnamomum camphora 36
Appendix 2 EU Biogeographical regions 46
Appendix 3 Images of Cinnamomum camphora 47
Appendix 4 Distribution maps of Cinnamomum camphora 52
6
Summary1 of the Express Pest Risk Analysis for Cinnamomum camphora (L.) J. Presl
PRA area: EPPO region (see https://www.eppo.int/ABOUT_EPPO/images/clickable_map.htm.).
Describe the endangered area:
The endangered area includes the following countries: Albania, Algeria, Bosnia and Herzegovina,
Croatia, Portugal, Georgia, Italy, Tunisia and Turkey and the following biogeographical regions:
the Mediterranean and Black Sea.
Currently, in the EPPO region, both the incidences of occurrence and their densities are limited (See
Appendix 1). Species distribution models conducted for this PRA suggest that there are no areas
within the EPPO region that have high suitability for establishment given the current climate
conditions, and that only limited areas in the Mediterranean and Black Sea biogeographical regions
have marginal suitability for the species (see Appendix 1). Given realistic climate change scenarios
(i.e., RCP8.5) expanded areas of suitable establishment are predicted for large parts of the Atlantic,
Continental, and Black Sea biogeographic regions. Thus, the future distribution of this potentially
problematic species may increase under climate change scenarios, particularly due to temperature
increases. However, current documentation of soil, habitat conditions, temperature, and
precipitation requirements is limited for C. camphora.
Habitats within the endangered area include evergreen forests, cleared land, mixed forests and moist
forests that are widespread within the EPPO region.
In the EPPO region Cinnamomum camphora is recorded (but not as invasive) in France, Portugal,
and Spain. In France, a single occurrence is recorded, apparently casual, growing near Bordeaux.
The species occurs in other European countries (for example, the Netherlands, Italy and Germany)
as planted specimens in gardens.
Main conclusions
Cinnamomum camphora presents a low phytosanitary risk for the endangered area within the EPPO
region with a moderate uncertainty. Cinnamomum camphora has been planted regularly for more
than 150 years as an ornamental and urban landscaping plant (McPherson 2003; Stubbs 2012, Firth
and Ensbey 2014) and is found as single specimens in managed areas (i.e., parks and gardens) in
the PRA area.
Further spread within and among countries is low with a moderate uncertainty. The overall
likelihood of C. camphora continuing to enter the EPPO region is moderate as the species is traded.
Entry and establishment
The pathways identified are: Plants or seed for planting (moderate likelihood of entry)
Within the EPPO region Cinnamomum camphora is recorded (but not as invasive) in France,
Portugal and Spain. In France, the species is regarded as casual. There is a single record of the plant
on GBIF (www.gbif.org) growing near Bordeaux. The species occurs in other European countries
(for example, the Netherlands, Italy and Germany) as planted specimens in gardens.
Deliberate planting of C. camphora seeds or young plants remains the most likely form of human
assisted spread. The small inedible drupes that hold the seeds currently are unlikely to be
1 The summary should be elaborated once the analysis is completed
7
accidentally spread via human operations. In addition, dispersal by frugivorous birds is likely to
occur.
Potential impacts in the EPPO region
Potential impact on biodiversity and ecosystem services in the EPPO region are likely to be low
with a moderate uncertainty. Considering the low likelihood of establishment and spread within the
EPPO region, due to the lack of suitable climate, soils and habitat, it is perceived that the impacts
of C. camphora under current climate conditions will be low compared to the current range of the
species. No impacts are envisaged on red list species and species listed in the Birds and Habitats
Directives in the near future though this could potentially change if the species establishes under
future climate conditions.
Given that this plant has been present in the EPPO region since at the turn 18th Century (Eaton 1912),
it appears at least some of the factors that influenced the Australian invasion are not present in the
EPPO region. The combination of climate, soils, and lack of cleared forest and abandoned land,
which represents the main types of habitats affected by near monotypic camphor stands in Australia,
is not common in the region. There may be limited areas susceptible to invasion that should be
monitored for natural colonisation of this potential invader.
Impacts of C. camphora invasions in the EPPO area are likely attenuated by current climatic
suitability. In areas suited to the spread and establishment of the species the main question is whether
we can expect an invasion similar to what has occurred in parts of Australia.
Climate change
By the 2070s, under climate change scenario RCP8.5, projected suitability for C. camphora in
Europe increases substantially. Much of Mediterranean and western Europe is predicted to become
suitable for the species including the countries Albania, Belgium, Bosnia and Herzegovina, Croatia,
France, Portugal, Georgia, Italy, Netherlands and Turkey.
The results of this PRA show that Cinnamomum camphora poses a low risk to the endangered
area (Mediterranean and Black Sea biogeographical regions) under current climatic
projections with moderate uncertainty.
The Expert Working Group recommends limited phytosanitary measures for this species given the
overall low phytosanitary risk within the endangered area:
• a thorough review of identity and establishment status of Cinnamomum species within the
endangered area,
• Cinnamomum camphora should be monitored for establishment and spread. Casual
occurrences should be eradicated,
• industry correctly labels species in trade, including hybrids,
• the PRA is reviewed every ten years or when significant new information (e.g. naturalisation
in the environment of the endangered area or ecological data) becomes available.
8
Phytosanitary risk for the endangered area
(current/future climate)
Pathway for entry
Plants for planting: Moderate/Moderate
Likelihood of establishment in natural areas: Low/High
Likelihood of establishment in managed areas: Moderate/High
Spread: Low/Low
Impacts (EPPO region)
Biodiversity: Low/Moderate
Ecosystem services: Low/Moderate
Socio-economic: Low/Moderate
High ☐ Moderate ☐ Low X
Level of uncertainty of assessment (current/future climate)
Pathway for entry
Plants for planting: Low/Moderate
Likelihood of establishment in natural areas: Moderate/High
Likelihood of establishment in managed areas: Moderate/High
Spread: Moderate/Moderate
Impacts (EPPO region)
Biodiversity: Moderate/High
Ecosystem services: Moderate/High
Socio-economic: Moderate/High
High ☐ Moderate X Low ☐
9
Express Pest Risk Analysis: Cinnamomum camphora (L.) J. Presl
Prepared by:
First draft: S. Luke Flory, University of Florida, Gainesville, FL. E-mail: [email protected]; tel.:
352-294-1581 (with support from Austin Young, [email protected])
Date:
Stage 1. Initiation
1. Reason for performing the PRA:
Cinnamomum camphora was identified as a species of interest during an EU-wide “horizon
scanning” effort, led by Roy et al. (2015), to identify potentially Invasive Alien Species (IAS)
and prevent and mitigate their ecological effects. They developed a ranked list of species that
are likely to be introduced, spread, and have significant impacts on biodiversity, and should be
further evaluated with risk assessment approaches. Subsequently, EPPO included the species
as one of concern in having the potential to establish and spread in novel areas within the next
ten years. Cinnamomum camphora was identified as 1 of 16 species with high priority for a
PRA given its known ecological impacts in its invasive range, coupled with the potential for
spread in natural areas within the EPPO region, and cost effectiveness of management efforts.
The species is a large tree native to Asia that has been intentionally introduced for ornamental,
timber, and industrial purposes in regions around the world. In some regions (e.g., South-
eastern Australia, South Africa, USA) C. camphora is often considered highly problematic
because of its significant effects on native biodiversity and forest regeneration. Initial
distribution maps indicated the potential occurrence of C. camphora is limited to southern areas
of the EPPO region under current climate conditions but the projected range is expected to
expand under future climate scenarios. In 2016, the species was prioritized (along with 36
additional species from the EPPO List of Invasive Alien Plants and a recent horizon scanning
study2) for PRA within the LIFE funded project “Mitigating the threat of invasive alien plants
to the EU through pest risk analysis to support the Regulation 1143/2014’. C. camphora was
one of 16 species identified as having a high priority for PRA.
PRA area:
The EPPO region (see https://www.eppo.int/ABOUT_EPPO/images/clickable_map.htm.).
2 http://ec.europa.eu/environment/nature/invasivealien/docs/Prioritising%20prevention%20efforts%20through%20horizon%20scanning.pdf
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Stage 2. Pest risk assessment
Taxonomy:
Cinnamomum camphora (L.) J. Presl (Kingdom Plantae; Subkingdom Tracheobionta;
Superdivision Spermatophyta; Division Magnoliophyta; Class Magnoliopsida; Subclass
Magnoliidae; Order Laurales; Family Lauraceae; Genus Cinnamomum).
(USDA http://plants.usda.gov/core/profile?symbol=CICA, Accessed 8-19-2016)
Basionym: Laurus camphora L.
EPPO Code: CINCA
Synonymy:
Camphora officinarum Nees; Camphora officinarum var. glaucescens A. Braun; Cinnamomum
camphora var. glaucescens (A. Braun) Meisn.; Cinnamomum camphoroides Hayata;
Cinnamomum nominale (Hats. & Hayata) Hayata; Persea camphora (L.) Spreng.
(Tropicos.org. Missouri Botanical Garden. 19 Aug 2016
<http://www.tropicos.org/Name/17805257>
Common names:
zhāng Chinese; 樟 Chinese; kamferboom Dutch; camphor English; camphor laurel English;
camphor tree English; majestic beauty camphor English (US); camphrier French; laurier du
Japon French; Kampferbaum German; albero della confora Italian; alloro canforato Italian;
laurocanfora Italian; kusu-no-ki Japanese; クスノキ Japanese; alcanforeira Portuguese;
камфорное дерево Russian; камфорный лавр Russian; коричник камфорный Russian;
alcanforero Spanish; kamferträd Swedish (EPPO Global Database, 2016)
Plant type: Evergreen large tree (Flora of China Vol. 7 Page 102, 167, 175)
Related species in the EPPO region: (from Botanical gardens) Cinnamomum glanduliferum
(Wall.) Meisn. Cinnamomum verum J.Presl, Cinnamomum japonicum Siebold, Cinnamomum
micranthum (Hayata)
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2. Pest overview
Introduction
Cinnamomum camphora is a large evergreen tree that is native to Southeast Asia (China and
Japan), but due to its commercial applications and use as landscaping species, has been
introduced to warmer climates on six continents. The species produces drupes that are readily
dispersed, primarily by birds, but also by waterways (Jordan 2011; Firth and Ensbey 2014).
Cinnamomum camphora is considered a noxious weed or invasive in several regions where it
has naturalized, including Australia (Firth, 1980a), USA (Florida), and South Africa, mostly
due to its tendency to dominate disturbed environments and exclude other species (Stubbs
2012; Firth and Ensbey 2014). Within the EPPO region, the species is sold as an ornamental
plant and is present in France, Germany, Ireland, Italy, Netherlands, Portugal and Spain (GBIF
2016; Eaton 1912), primarily as individually planted specimens although some of these
occurrences may not be outdoors. Currently, in the EPPO region, both the incidences of
occurrence and their densities are apparently limited. Species distribution models conducted
for this PRA suggest that there are no areas within the EPPO region that have high suitability
for establishment given the current climate conditions, and that only limited areas in the
Mediterranean and Black Sea biogeographical regions and have marginal suitability for the
species (see Appendix 1 and Appendix 2). Given realistic climate change scenarios (i.e.,
RCP8.5) expanded areas of suitable establishment are predicted for large parts of the Atlantic,
Continental, and Black Sea biogeographic regions. Thus, the future distribution of this
potentially problematic species may increase under climate change scenarios, particularly due
to increases in minimum annual temperatures. However, current documentation of species soil,
habitat conditions, temperature, precipitation requirements is limited for C. camphora.
Environmental requirements
Relatively limited research has been conducted on the ecophysiological limits of C. camphora.
The species is most often distributed in moist tropical and subtropical environments but
tolerates a reported broad range of precipitation and temperature conditions. Once established,
adult C. camphora are considered hardy (USDA hardiness zones 9B through to 11), and Firth
(1981) noted that it grows well in a wide range of environments throughout the world.
However, there are limits to the conditions where C. camphora can survive. Both Yan De-qi et
al. (2007) and You Yang et al. (2008) demonstrated that seedlings are damaged at temperatures
of -10 oC and lower. However, neither study determined the temperature limit of the species,
and large trees in Japan are known to survive 70-80 days per year of temperatures as low as -
11 oC (Kew 1899). The preferred mean annual temperatures are reported to be around 14-27 oC. One source indicates that C. camphora can survive at altitudes of up to 1350-1800 meters
and Gupta (1982) observed the species thriving at 2000 m asl in Nilgris, India. There is some
indication that the species can tolerate annual rainfall of 640-4030 mm (Agroforestree
Database, 2009) but Firth (1981) reported that C. camphora in Australia exhibited lower
colonization in areas subject to rainfall less than 1400 mm. Under natural forest canopy in the
native range in China, experimental research showed low germination and seedling growth
(Chen et al 2004). It occurs on a variety of soils, although the development of minor
deficiencies on alkaline soils has been reported and the species will not grow on soils that are
waterlogged for extended periods (Gilman 2016; Kew 1899). Firth (1979) observed that C.
camphora was most often found on well-drained, red clay soils (these are the acidic, krasnozem
soils of cleared rainforest regions) in Australia. In sum, while C. camphora is broadly
12
distributed in some regions, it is limited by temperature (cold in particular) and soil moisture
conditions.
Habitats
Cinnamomum camphora is native to broadleaved evergreen, mixed deciduous and moist
rainforests with warm, moist climates. However, in its introduced ranges it is most often found
in heavily disturbed areas, particularly where forests have been cleared, plantations (e.g.,
banana in Australia) have been abandoned, or in cases where pastures are overgrazed or
abandoned. In South Africa, the species invades forest margins, coastal bush and river banks
(Henderson 2001). See also the environmental requirements section above.
Identification
Cinnamomum camphora is a large evergreen tree reaching heights of 30 meters and diameter
at breast height of 1.5-2.0 m (See Figure 1 and 2, Appendix 3). It is strongly camphor-scented,
including bark, leaves, branches. The bark is yellow-brown, and irregularly and longitudinally
fissured (see Figure 3, Appendix 3). Branchlets are brownish, terete, and glabrous. Terminal
buds are broadly ovoid with bud scales broadly ovate or suborbicular and sparsely sericeous
outside. Leaves waxy in appearance, alternate; petiole slender, 2-3 cm, concave-convex, and
glabrous (See Figure 4, Appendix 3). The leaf blade is yellow-green or gray-green and glabrous
on both surfaces or sparsely puberulent abaxially only when young. Flowers are bisexual, tiny,
with a white membranaceous perianth, and are organised in panicules that are shorter than the
leaves. The fruit is a purple-black, ovoid or subglobose drupe, 6-8 mm in diameter, subtended
by a small cupule (See Figure 5, Appendix 3). The plant features bract-covered buds and long,
slender petioles (Flora of China, n.d.). Cinnamomum camphora can be distinguished from C.
glanduliferum for example by leaf nervation. The former species typically has three main
nerves to its leaves whereas the latter is pinnately nerved.
Symptoms
The primary symptom of C. camphora establishment in introduced ranges is the tendency to
displace native vegetation, often to the extent of creating near monotypic thicket (Firth and
Ensbey 2014). However, it should be noted that in many cases the formation of dense stands
has occurred after land has been cleared, poorly managed (e.g., overgrazing), or abandoned.
Once a monospecific stand of C. camphora forms, the ecological and economic value of land
is diminished, especially because the species is considered difficult and costly to remove. Adult
trees are highly competitive and produce a large, shady canopy that can suppress native
seedlings (Firth and Ensbey 2014). Cinnamomum camphora may contribute to soil erosion on
steep slopes and stream banks due to its shallow root system (Scott 1999). Limited studies in
Australia have linked the fallen leaves of C. camphora to die-offs of aquatic animals in stream
ecosystems. One such study showed that the leaf litter of C. camphora has detrimental effects
on the densities of some native shredding invertebrates and inhibited growth rates of a common
shredding caddisfly (Davies 2009). Thus, there is some evidence that C. camphora invasions
can result in altered community structures and ecological functions. However, the extent of
ecological effects of invasions appears highly variable, and may also be a symptom of land
degradation.
13
Existing PRAs
Hawaii: Pacific Island Ecosystems at Risk (PIER). This risk assessment predicts the likelihood
of invasions of species in Australia, Hawaii, and the high islands of the Pacific. Results are also
sometimes modified for the State of Florida. The risk assessment for Hawaii scored C.
camphora as 7.5, indicating that the species poses a significant risk of becoming a problematic
invader (PIER 2005).
Spain: Andreu & Vilà (2009) performed two different types of Weed Risk Assessments
(WRAs) for 80 species for Spain, including C. camphora. For both the "Australian" WRA and
"Weber and Gut" methodologies C. camphora scored an 11, indicating low risk of invasion
(Andreu & Vilà, 2009).
Europe (overall): The current PRA is being conducted under the LIFE project (LIFE15 PRE
FR 001) within the context of European Union regulation 1143/2014, which requires that a list
of invasive alien species (IAS) be drawn up to support future early warning systems, control
and eradication of IAS.
Socio-economic benefits
Cinnamomum camphora has a history of use as a landscaping, ornamental, shade, and timber
tree. Mature trees are attractive and hardy, and provide dense shade, making them ideal for
parks, greenways, and landscapes. The wood of C. camphora is traded around the world to be
used for products such as furniture and mulch. Camphor oil, derived from C. camphora, was
historically harvested in eastern Asia to be used for medicinal, insecticidal, insect repellent,
sanitary, and religious/ceremonial purposes (Stubbs 2012). In the 1860s, camphor began to be
harvested for the creation of the nitrocellulose-based plastic that would become known as
celluloid. At one point in the early twentieth century, as much as 70% of all camphor production
was used for celluloid (Eaton 1912), with a primary use being the production of film. In the
early part of the 20th century, industrial use of C. camphora declined as alternatives and
synthetics emerged (PlantUse 2016). Although naturally derived camphor oil has been largely
replaced on the market by synthetic versions, there exists a niche market for the product sourced
from C. camphora (Scott 1999). More recently, leaves of the species have been used in the
biosynthesis of silver and gold nanoparticles (Huang 2007). In South Africa, C. camphora is
used as a foraging plant in bee farming. Cinnamomum camphora leaves have been used as a
phytoremediation for the effective removal of Pb(II) from aqueous solutions (Chen et al.,
2010).
Camphor tree continues to be available at online nurseries, e.g., in the UK:
http://www.planfor.co.uk/buy,camphor-tree,9295,EN
http://www.jungleseeds.co.uk/contents/en-uk/d20.html (seeds online)
and in Italy:
http://www.gorinipiante.it/en/mediterranean-plants/cinnamomum-camphora-2-00-2-50-clt-
30-35_1959997703_en_gb-detail
3. Is the pest a vector? Yes
Cinnamomum camphora is a host for Xyleborus glabratus (redbay ambrosia beetle), which
carries the spores of Rafaela lauricola, the fungus that causes laurel wilt disease. Laurel wilt
14
disease is a pathogen with the potential to devastate Persea borbonia (redbay), avocado
(Persea americana), and other related species (Mayfield et al. 2008). Recently, the disease has
led to mass redbay tree deaths in the southeastern USA (Mayfield et al 2008) and was first
discovered on an avocado tree in Florida in 2007 (EPPO 2016). Both X. glabratus and R.
lauricola are absent in the EPPO region, but R. lauricola can be transferred from diseased trees
to insects other than X. glabratus and still lead to tree mortality. The PRA regions main area of
risk are probably the laurel forests (including Lauraceae genera such as Apollonias, Ocotea,
Persea) found in the Azores, Madeira (PT) and Islas Canarias (ES) – although, their
susceptibility is unknown (EPPO 2016). EPPO also reports “avocado is not widely grown in
the EPPO region but is of economic importance at least in Israel and Spain.” Currently, there
are no cultivars of avocado immune to laurel wilt disease. C. camphora has been reported as a
host of Phytophora ramorum (Rooney et al., 2013).
4. Is a vector needed for pest entry or spread? No
No vector is necessary for C. camphora to enter into or spread within the PRA area.
5. Regulatory status of the pest
USA:
Category 1 (capable of "...altering native plant communities by displacing native species,
changing community structures or ecological functions, or hybridizing with natives.") on the
Florida Exotic Pest Plant Council’s 2015 List of Invasive Plant Species (fleppc.org). Prohibited
in Miami-Dade County, Florida, USA.
Australia:
New South Wales: Class 4 (locally controlled weed). The growth and spread of this species
must be controlled according to the measures specified in a management plan published by the
local control authority and the plant may not be sold, propagated, or knowingly distributed (in
the Ballina, Bellingen, Blue Mountains, Byron, Clarence Valley, Hornsby, Ku-ring-gai,
Kyogle, Lismore, Nambucca, Richmond Valley, Ryde, Tweed and Willoughby local authority
areas).
Queensland: Class 3 (primarily an environmental weed). A pest control notice may be issued
for land that is, or is adjacent to, an environmentally significant area (throughout the entire
state). It is also illegal to sell a declared plant or its seed in this state.
South Africa:
Category 1 (i.e. requires compulsory control) species in 4 out of the 9 South African Provinces
(KwaZulu-Natal, Limpopo, Eastern Cape and Mpumalanga), but not subject to legislation
elsewhere. In the Western Cape Province listed as category 3 species meaning that a permit is
required for transport and use.
15
6. Distribution
Contine
nt
Distribution (list countries, or
provide a general indication,
e.g. present in West Africa)
Provide comments on the pest
status in the different countries
where it occurs (e.g. widespread,
native, introduced)
Reference
Africa Canary Islands, Madagascar,
South Africa, Egypt, Ghana,
Kenya, Togo, Tanzania,
Zimbabwe
Introduced and established.
Cultivated in Madagascar Henderson
(2007), Kew
(1899), USDA
(2016). North
America
United States: Florida, North
Carolina, South Caroline,
Georgia, Alabama, Mississippi,
Louisiana, Texas, California
Introduced. Widespread primarily in
parks and gardens and disturbed
areas, often listed as invasive
USDA (2016),
Langeland et al.
(2008),
Tropicis.org
(2016). South
and
Central
America
Bolivia, Brazil, Costa Rica, El
Salvador, Honduras, Puerto
Rico, Trinidad and Tobago,
Venezuela,
Introduced. Widespread primarily in
landscaping and disturbed areas,
often listed as invasive
Kew (1899),
USDA (2016).
Asia China, Japan, South Korea,
Vietnam, Bangladesh, Hong
Kong, Indonesia, India, Laos,
Malaysia, Saudi Arabia, Taiwan,
Sri Lanka
Native and widespread in SE Asia. Eaton (1912),
Stubbs (2012),
USDA (2016),
GBIF (2016).
Europe France, Portugal, Spain. Introduced, currently not invasive.
In France, the species is regarded as
casual. There is a single record of the
plant on GBIF growing on a dune
system at the Cap de Ferret, near
Bordeaux.
The species occurs in European
countries (for example, the
Netherlands, Italy and Germany) as a
planted species in botanical gardens.
Eaton 1912,
GBIF (2016)
Personal
Communication
G. Fried (2016);
Maniero (2000).
Oceania Australia, French Polynesia,
Hawaii, New Zealand
Invasive and problematic, primarily
in Australia where it is under
chemical and mechanical control.
GBIF (2016),
Stubbs (2012),
USDA (2016).
Introduction
Cinnamomum camphora is native to much of eastern, and primarily southeastern, Asia,
including southern China, Indonesia, Vietnam, Korea, and southern Japan. It was introduced
intentionally in many regions of the world for ornamental, landscaping, and maybe most often
for commercial purposes to produce camphor oil. The species is most problematic and
widespread in Australia and Florida, USA (See Figure 1, Appendix 4).
16
North America
Introduced to Florida as early as 1870 and one nursery alone was selling 15,000 trees annually
in the early twentieth century (Eaton 1912). In 1880, the USDA distributed seed and young
trees to be planted as windbreaks and ornamentals, resulting in rapid and widespread
distribution in the southern and principally southeastern USA (Eaton 1912). In the 1900s, C.
camphora was regularly planted as a street tree in California (McPherson 2003). The USDA
currently reports C. camphora established in North Carolina, South Carolina, Georgia, Florida,
Alabama, Mississippi, Louisiana, Texas, and California (USDA 2016).
Asia
Cinnamomum camphora is native to subtropical East Asia, specifically Japan, China, Vietnam,
and Taiwan (Stubbs 2012). By 1912 it was being cultivated in Malaysia, Sri Lanka (Ceylon as
detailed in Eaton, 1912), India, and Myanmar (Burma, as detailed in Eaton, 1912) (Eaton
1912). There are no available reports to indicate that C. camphora is problematic in its native
range.
Europe
Prior to 1912, C. camphora was grown as an ornamental in Italy and other southern European
countries near the Mediterranean (Eaton 1912). By 1899 the species was reported as ‘thriving’
in Southeastern France (Kew 1899). However, more recent evidence of C. camphora occurring
outside cultivation in Europe is very limited. In France the species is regarded as casual. There
is a single record of the plant on GBIF growing on a dune system at the Cap de Ferret, near
Bordeaux. The majority of literature that mentions the species refers to a lone tree, specimens
in botanical gardens, and urban ornamentals. In Switzerland, the is reference to the C.
camphora but the species has not become naturalised (Walther, 2000).
Oceania
Cinnamomum camphora was introduced to Australia in the late 1820s, but the earliest planting
outside of a botanical garden occurred in the 1870s (Stubbs 2012). By the late 1990s, it had
become a major environmental problem in eastern Australia (Firth, 1980b; Stubbs 2012). In
Queensland and New South Wales the species is prohibited from sale and propagation. In
eastern Australia “extensive monospecific stands have developed along the banks of creeks
and rivers preventing regeneration of native tree and shrub species. It is particularly well-
adapted to areas formerly covered by rainforest (PIER 2012).”
Central and South America
By 1899, C. camphora was reported as flourishing in Buenos Aires, Argentina (Kew 1899).
By 1912 it was under cultivation in Jamaica and the West Indies (Eaton 1912).
Africa
There have been various efforts to cultivate the species as an ornamental, agricultural, and
silvicultural plant in Africa. In 1896, C. camphora was shipped from East Africa to the British
Royal Gardens, Kew (Botanical Enterprise in East Africa 1896). Field records from 1979 to
2000 in South Africa, Lesotho, and Swaziland (consolidated by Henderson 2007) show C.
camphora listed as invasive in forest habitats, savannah biome, and grassland biome. However,
the “total weighted abundance” for the species is consistently rated very low within the same
area (Henderson 2007). By 1899 the species was reported as ‘thriving’ in Egypt (Kew 1899).
17
7. Habitats and their distribution in the PRA area
EUNIS habitats from: European Environment Agency (2016)
Habitats EUNIS
habitat
types
Status of habitat (eg
threatened or
protected)
Present in
PRA area
(Yes/No)
Comments (e.g.
major/minor
habitats in the PRA
area)
Reference
Wooded
areas
G:
Woodland,
forest and
other
wooded land
Protected pro parte:
e.g. Annex 1
G: 41.181, 41.184,
41.6, 41.77, 41.85,
41.9, 41.1A X 42.17
41.1B, 42.A1 44.17
44.52, 44.7 44.8, 45.8,
41 .7C, 45.1, 45.2,
45.3, 45.5, 45.61 to
45.63, 45.7
Yes
Major habitats
within PRA area.
EWG
opinion
Heathland F: Heathland
and scrub
Protected pro parte:
e.g. Annex 1
F: 32.216, 32.11
Yes Major habitats
within PRA area.
EWG
opinion
Cinnamomum camphora is native to broadleaved evergreen, mixed deciduous and moist
rainforests with warm, moist climates. However, in its introduced ranges it is most often found
in heavily disturbed areas, particularly where forests have been cleared, plantations (e.g.,
banana in Australia) have been abandoned, or in cases where pastures are overgrazed or
abandoned. In South Africa, the species invades forest margins, coastal bush and river banks
(Henderson 2001). In the EPPO region, habitats include evergreen forests, cleared land, mixed
forests and moist forests.
Woodland habitat is found throughout the PRA area. The abundance and diversity of heath
and scrub habitats is uneven across the different regions of Europe, with a higher
representation in the Mediterranean, the Macaronesian and in the Atlantic regions, where a
substantial number of genera of legumes, ericaceous and other sub-shrubs are highly
diversified
18
8. Pathways for entry
Possible pathways
(in order of importance)
Pathway: Plants for planting
Short description explaining
why it is considered as a
pathway
Cinnamomum camphora has a history of deliberate planting for
ornamental and other purposes at both urban (e.g., city streets) and
rural (e.g., abandoned fields) sites (Stubbs 2012). The seeds and
young plants are available on the internet informally and through
nurseries. Seed of C. camphora is available for purchase from outside
of the EPPO region. Websites often advertise that seeds are shipped
worldwide (for example http://www.seedscollector.com/50-seeds-
camphor-tree--cinnamomum-campho50.html).
Many of the traders misidentify Cinnamomum camphora with other
Cinnamomum spp, e.g. C. glanduliferum.
Is the pathway prohibited in
the PRA area?
There is no evidence of regulation within the PRA area.
Has the pest already
intercepted on the pathway?
Yes because it is the commodity itself.
What is the most likely stage
associated with the pathway?
All growth forms except for large trees are associated with this
pathway, including trade of seeds.
What are the important
factors for association with
the pathway?
Seed suppliers (http://www.seedscollector.com/50-seeds-camphor-
tree--cinnamomum-campho50.html and online marketplaces (e.g.,
ebay.com)
Is the pest likely to survive
transport and storage in this
pathway?
Only through intentional introductions by humans. However, given
the seeds can be dispersed by birds and waterways, any tree
producing drupes within the EPPO region could be the origin of a
new establishment, especially trees that are planted near watercourses
and in non-urban habitats.
Can the pest transfer from
this pathway to a suitable
habitat?
Yes, through direct human actions. The species responds well to
anthropogenic disturbances in rural (e.g. agriculture) areas. Planted
individuals may have the potential to be spread via birds or water
dispersed seeds.
Will the volume of
movement along the pathway
support entry?
Any volume of movement will support entry. However, there is no
information on the amount the species is traded (imported) into the
EPPO region from Asia or the USA.
Will the frequency of
movement along the pathway
support entry?
Yes, see question ‘Will the volume of movement along the pathway
support entry?’
Likelihood of entry Low ☐ Moderate X High ☐
19
Rating of uncertainty Low X Moderate High ☐
Do other pathways need to be considered?
No
9. Likelihood of establishment in the natural environment PRA area
In the native range the species is generally limited to approximately 10-36 °N and 105-130 °E
and in warm, moist climatic zones (CABI 2016). In areas where minimum temperatures dip
below -10 °C, C. camphora seedlings experience damage (Yan De-qi et al 2007; You Yang et
al 2008). Therefore, establishment within the PRA area is less likely where such temperatures
are common. The most likely area of establishment is the Mediterranean and Black Sea
biogeographical region. Habitats within the endangered area include Mediterranean woodlands
and scrublands where laurels are known to grow.
Habitats within the endangered area include evergreen forests, cleared land, mixed forests and
moist forests that are widespread within the EPPO region.
Rating of the likelihood of establishment in the natural
environment Low X Moderate High ☐
Rating of uncertainty Low ☐ Moderate X High ☐
10. Likelihood of establishment in managed environment in the PRA area
Cinnamomum camphora has been planted regularly for more than 150 years as an ornamental
and urban landscaping plant (McPherson 2003; Stubbs 2012, Firth and Ensbey 2014) and is
found as single specimens in managed areas (i.e., parks and gardens) in the PRA area.
Relatively limited research has been conducted on the ecophysiological limits of C. camphora.
The species is most often distributed in moist tropical and subtropical environments but
tolerates a reported broad range of precipitation and temperature conditions. There are limits
to the conditions where C. camphora can survive. Both Yan De-qi et al. (2007) and You Yang
et al. (2008) demonstrated that seedlings are damaged at temperatures of -10 oC and lower and
therefore this would limit its natural establishment within much of Europe. The preferred mean
annual temperatures are reported to be around 14-27 oC.
Cinnamomum camphora occurs on a variety of soils, although the development of minor
deficiencies on alkaline soils has been reported and the species will not grow on soils that are
waterlogged for extended periods (Gilman 2016; Kew 1899). Firth (1979) observed that C.
camphora was most often found on well-drained, red clay soils (these are the acidic, krasnozem
soils of cleared rainforest regions) in Australia.
Currently, in the EPPO region, both the incidences of occurrence and their densities are
apparently limited. Species distribution models conducted for this PRA suggest that there are
no areas within the EPPO region that have high suitability for establishment given the current
climate conditions, and that only limited areas in the Mediterranean and Black Sea
biogeographical regions and have marginal suitability for the species (see Appendix 1 and
Appendix 2).
20
Rating of the likelihood of establishment in the managed
environment Low ☐ Moderate X High
Rating of uncertainty Low Moderate X High ☐
11. Spread in the PRA area
Natural spread
The species spreads primarily through frugivorous birds that feed on the drupes and disperse
seeds widely, with little effect on seed viability (Stubbs 2012, Jordan 2011, Firth and Ensbey
2014). Firth (1979), suggested other fauna also consume and spread the seeds, but he did not
give the species names. He also indicated the possibility of spread by water due to the fact the
seed can survive up to 40 days in water. It has been reported that seeds can remain viable for
up to 3 years and germination can extend across a period of 4 to 20 weeks (Firth and Ensbey
2014). However, experimental work demonstrated that seed survival was less than 1 % after 12
months (Panetta 2001). Under natural forest canopy in the native range in China, experimental
research showed low germination and seedling growth (Chen et al 2004), but establishment
rates in the invaded range (eg. Australia) are high. Drupes also can be spread by flowing water,
streams (Queensland Government 2016).
Human assisted spread
Cinnamomum camphora is planted for landscaping and was historically farmed for camphor oil
and timber production (Stubbs 2012). After the mid-1940s, large plantations were established
in Japan and China. It has been cultivated outside of its native range, including in Sri Lanka,
southern India, eastern Africa, and the USA (Eaton 1912), but there are no documented sites of
camphor production within the EPPO region. The plant is present in Europe primarily due to
ornamental or landscaping plantings.
Camphor tree continues to be available at online nurseries, e.g., in the UK:
http://www.planfor.co.uk/buy,camphor-tree,9295,EN
http://www.jungleseeds.co.uk/contents/en-uk/d20.html (seeds online)
and in Italy:
http://www.gorinipiante.it/en/mediterranean-plants/cinnamomum-camphora-2-00-2-50-clt-
30-35_1959997703_en_gb-detail
Deliberate planting of C. camphora seeds or young plants remains the most likely form of
human assisted spread. The small inedible drupes that hold the seeds currently are unlikely to
be accidentally spread via human operations.
A low rating for magnitude of spread has been given as even though the species has been
reported to spread by water there is no evidence that the species grows near riparian systems
in the EPPO region. In addition, it is unlikely that active frugivore fauna that is capable of
spreading seeds of the plants dimensions are present in the EPPO region.
Rating of the magnitude of spread Low X Moderate High ☐
Rating of uncertainty Low Moderate X High ☐
21
12. Impact in the current area of distribution
12.01 Impacts on biodiversity and ecosystem patterns
Cinnamomum camphora can form apparently monotypic thickets and exclude native vegetation
(Firth and Ensbey 2014). Its large shady canopy and dense shallow roots may suppress the
establishment and growth of seedlings in the immediate vicinity of the tree (Firth and Ensbey
2014). However, a scientific review committee assembled by the Government of New South
Wales, Australia found little evidence to support the claims of adverse impacts on native taxa
from the toxic chemotypes found in C. camphora’s leaf exudates (NSW Scientific Committee
2004). Cinnamomum camphora actually may be beneficial for bird populations in Australia by
providing food and habitat on recently cleared land (Date 1991; Kanowski and Catterall, 2008).
Experiments have found C. camphora has a detrimental effect on densities of native
invertebrates and impairs growth rates of a common shredding caddisfly, possibly due to the
chemicals in the leaf litter dropped into streams (Davies 2009). The root system of C. camphora
is thought to poorly hold soil in place around streams and drainage ditches, resulting in bank
destabilisation (Scott 1999; Firth and Ensbey 2014).
To-date there are no impacts recorded on red list species and species listed in the Birds and
Habitats Directives.
Control measures
Mechanical control
Smaller trees can be cut down easily, but the stumps can rapidly resprout so they must be
grinded out or treated chemically (Firth 1981). Bulldozing is effective at removing the entire
tree and can be done without prior treatments, but is expensive (Firth and Ensbey 2014).
However, care should be taken during the mechanical removal of entire trees as the resulting
soil disturbance can encourage further invasions of C. camphora or other non-native species
(Firth and Ensbey 2014). Continuous mowing will kill resprouting shoots, and burning can be
effective, but larger trees often resprout (Queensland Government 2016).
Chemical control
This section lists chemicals that have been cited for use against the species. This does not mean
the chemicals are available or legal to use and countries should check to ensure chemicals are
licensed for use in their country. Depending on the type of herbicide and size of the tree, control
can be achieved through cut stump, stem injection, basal bark, or foliar spray application
techniques (Firth and Ensbey 2014). Firth (1981) recommends spraying young plants with a 0.3
% mixture of 2,4-D and 2,4,5-T in water. Basal bark and cut stump applications are
recommended for larger trees, with a higher concentration; 3 to 5 % herbicide in oil. See table
below for recent recommendations:
Adapted from: State of Queensland, Department of Agriculture and Fisheries, 2016. Camphor laurel
Factsheet. (note: This section lists chemicals that have been cited for use against the species.
This does not mean the chemicals are available or legal to use and countries should check to
ensure chemicals are licensed for use in their country).
22
Herbicide Rate Comments
Triclopyr 300 g/L + picloram
100 g/L (e.g. Conqueror)
350–500
mL/100 L
water
High-volume spray for trees up to 3 m tall;
higher rate for trees >
2 m tall.
500 mL/10 L
water
High concentration/low volume application (gas
gun or sprinkler sprayer). Trees less than 1.5 m
high which are able to be sprayed from all sides.
Use high volume application on larger bushes.
Triclopyr 300 g/L + picloram
100 g/L + aminopyralid 8 g/L
(e.g. Grazon Extra)
350–500
mL/100 L
water
High concentration/low volume application (gas
gun or splatter gun). Trees less than 1.5 m high.
500 mL/10 L
water
High concentration/low volume application (gas
gun or splatter gun). Trees less than 1.5 m high.
Use high volume application on larger bushes.
Triclopyr 600 g/L (e.g. Garlon
600)
170 mL/100 L
water
High-volume foliar spray for trees up to 3 m
tall.
Triclopyr 600 g/L (e.g. Garlon
600)
1 L in 60 L
diesel
Basal bark trees to 10 cm diameter or cut stump
trees to basal bark size or greater.
Triclopyr 200 g/L + picloram
100 g/L (e.g. Slasher)
Mix 1 part
herbicide with
4 parts water
Stem injection application. Consult label for
detailed instructions.
Triclopyr 200 g/L + picloram
100 g/L + aminopyralid 25
g/L (e.g. Tordon
RegrowthMaster)
Mix 1 part
herbicide with
4 parts water
Stem injection application. Consult label for
detailed instructions.
Glyphosate 360 g/L (e.g.
Roundup Biactive)
2 mL of 1:1
mix with water Stem injection for trees up to 25 cm in diameter.
2 mL undiluted Stem injection for trees 25−60 cm in diameter
Glyphosate 360 g/L
(Roundup®) Undiluted 4ml per drill hole / axe cut
Glyphosate 360 g/L
(Roundup®)
1 part
glyphosate to
50 parts water
Spray seedlings and coppice shoots.
Glyphosate 360 g/L
(Roundup®)
1 part
glyphosate to
1.5 parts water
Cut stump/scrape stem application for saplings.
Stem injection application large trees and
shrubs.
Picloram 100 g/L + Triclopyr
300 g/L + Aminopyralid 8 g/L
(Grazon Extra®)
350 or 500 mL
per 100 L
water
Use higher rate on trees over 2 m tall. Apply as
a thorough foliar spray.
Picloram 44.7 g/kg +
Aminopyralid 4.47 g/L
(Vigilant II ®)
Undiluted
Cut stump/stem injection application. Apply a
3–5 mm layer of gel for stems less than 20 mm.
Apply 5 mm layer on stems above 20 mm.
Biological control
There are no known biological control agents for management of C. camphora, and no current
efforts to develop agents.
A high rating for impact in the current area of distribution has been given due to the plants
impact on invertebrate populations. The EWG hold the opinion that dense stands of C.
23
camphora can have a significant impact on native biodiversity. A moderate uncertainty is
given to reflect that much of the information on impacts is currently unsupported by scientific
studies.
Rating of the magnitude of impact in the current area
of distribution Low ☐ Moderate ☐ High X
Rating of uncertainty Low Moderate X High ☐
12.02. Consider the negative impact the pest may have on categories of ecosystem services
Ecosystem service Does the IAS
impact on this
Ecosystem
service? Yes/No
Short description of impact Reference
Provisioning Yes May inhibit growth of more desirable
forest species.
Firth and
Ensbey, 2014.
Regulating Yes Experiments have found C. camphora
has a detrimental effect on densities of
native invertebrates and impairs
growth rates of a common shredding
caddisfly, possibly due to the
chemicals in the leaf litter dropped
into streams.
May suppress biodiversity of trees
herbaceous plants and aquatic
organisms.
Davies 2009;
Firth and
Ensbey, 2014;
Victoria State,
Australia 2016.
Supporting Yes, but no
documented effect. Given the formation of apparently
monotypic thickets and exclusion
of native vegetation, it is expected
there are effects on nutrient cycling
and habitat stability.
EWG opinion
Cultural Yes Impacts on tourism through the
poisonous qualities of all parts of the
plant. In addition, the root structure
may damage cultural sites.
Victoria State,
Australia 2016.
Rating of the magnitude of impact in the current area
of distribution Low ☐ Moderate ☐ High X
Rating of uncertainty Low ☐ Moderate X High ☐
24
12.03. Describe the adverse socio-economic impact of the species in the current area of
distribution
Economic impacts
In heavily invaded areas of Australia, where C. camphora stands have established in former
rainforest sites, restoration of native forest has been documented to be costly (Kanowski and
Catterall, 2007).
Removal of large trees is expensive and C. camphora often regenerates after felling (Firth and
Ensbey 2014). Other websites provide additional anecdotes of economic effects such as
devaluation of grazing land (eg. Victoria State Australia, 2016), but many of these impacts are
very general and non-specific to the invader. Kanowski and Catterall (2007) estimate costs of
removing trees in rainforest habitats in New South Wales, Australia, vary from 5 000 – 30 000
$AUS/ha.
Human activities
There is little evidence of disruption to human activities due to the presence of C. camphora.
It is often planted as a shade and timber tree, and its desirable qualities have been noted (Stubbs
2012). All parts of C. camphora are poisonous to humans and can cause allergies, nausea,
vomiting, respiratory distress (Johnson, 2006). There have also been reported effects on leisure
activities, but these are generally unsubstantiated.
Rating of the magnitude of impact in the current area
of distribution
Low Moderate X High
Rating of uncertainty Low Moderate X High
13. Potential impact in the PRA area
Potential impact on biodiversity and ecosystem services in the EPPO region are likely to be
low with a moderate uncertainty. Considering the low likelihood of establishment and spread
within the EPPO region, due to the lack of suitable climate, soils and habitat, it is perceived
that the impacts of C. camphora under current climate conditions will be low compared to the
current range of the species. No impacts are envisaged on red list species and species listed in
the Birds and Habitats Directives in the near future though this could potentially change if the
species establishes under future climate conditions.
Given that this plant has been present in the EPPO region since at the turn 18th Century (Eaton
1912), it appears at least some of the factors that influenced the Australian invasion are not
present in the EPPO region. The combination of climate, soils, and lack of cleared forest and
abandoned land, which represents the main types of habitats affected by near monotypic
camphor stands in Australia, is not common in the region. There may be limited areas
susceptible to invasion that should be monitored for natural colonisation of this potential
invader.
Impacts of C. camphora invasions in the EPPO area are likely attenuated by current climatic
suitability. In areas suited to the spread and establishment of the species the main question is
whether we can expect an invasion similar to what has occurred in parts of Australia.
25
C. camphora is poisonous to humans and can cause allergies, nausea, vomiting, respiratory
distress (Johnson, 2006).
Will impacts be largely the same as in the current area of distribution? No
13.01. Negative environmental impacts with respect to biodiversity and ecosystem patterns and
processes
If No
Rating of the magnitude of impact in the area of potential
establishment Low X Moderate ☐ High ☐
Rating of uncertainty Low ☐ Moderate X High ☐
13.02. Negative impact the pest may have on categories of ecosystem services
If No
Rating of the magnitude of impact in the area of potential
establishment Low X Moderate ☐ High ☐
Rating of uncertainty Low ☐ Moderate X High ☐
13.03 Socio-economic impact of the species
If No
Rating of the magnitude of impact in the area of potential
establishment Low X Moderate ☐ High ☐
Rating of uncertainty Low ☐ Moderate X High ☐
14. Identification of the endangered area
Currently, in the EPPO region, both the incidences of occurrence and their densities are
apparently limited (See Appendix 1). Species distribution models conducted for this PRA
suggest that there are no areas within the EPPO region that have high suitability for
establishment given the current climate conditions, and that only limited areas in the
Mediterranean and Black Sea biogeographical regions and have marginal suitability for the
species (see Appendix 1.). Given realistic climate change scenarios (i.e., RCP8.5) expanded
areas of suitable establishment are predicted for large parts of the Atlantic, Continental, and
Black Sea biogeographic regions. Thus the future distribution of this potentially problematic
species may increase under climate change scenarios, particularly due to increases in minimum
annual temperatures. However, current documentation of species soil and habitat conditions,
and temperature and precipitation requirements is limited for C. camphora.
Habitats within the endangered area include evergreen forests, cleared land, mixed forests and
moist forests that are widespread within the EPPO region.
26
15. Climate change
15.01. Define which climate projection you are using from 2050 to 2100*
Climate projection RCP 8.5 2070
15.02 Which component of climate change do you think is most relevant for this organism?
Temperature (yes) Precipitation (yes) C02 levels (yes)
Sea level rise (no) Salinity (no) Nitrogen deposition (yes)
Acidification (no) Land use change (yes)
27
Are the introduction pathways likely to change due to climate
change? (If yes, provide a new risk and uncertainty score) Reference
Import for ornamental planting may increase as the range of suitable
area for cultivation is predicted to expand within the EPPO region.
The score for risk under predicted future climate conditions will not
change but the uncertainty score will increase.
Risk = Moderate Uncertainty = Moderate
EWG opinion; Appendix 1
Is the risk of establishment likely to change due to climate
change? (If yes, provide a new risk and uncertainty score) Reference
The likelihood of establishment could increase with higher
temperatures and greater rainfall in some areas. A primary concern
would be fewer low temperature events, given that it is know that -
10 °C has negative effects on C. camphora. Climate change
predictions suggest the species will be capable of more readily
establishing around the Atlantic, Western Continental, and the Black
Sea biogeographic regions.
Therefore, new scores for risk and uncertainty for predicted future
climate conditions, based on changes in temperature and
precipitation is:
Risk = High Uncertainty = High
Other important elements of change, including land-use change and C02 levels are not included in the above scoring.
(Yan De Qi et al. 2007; You
Yan et al 2008).
Is the risk of spread likely to change due to climate change? (If
yes, provide a new risk and uncertainty score) Reference
The risk of spread is unlikely to change as a result of climate
change.
EWG opinion
Will impacts change due to climate change? (If yes, provide a
new risk and uncertainty score) Reference
With increasing temperatures it is possible C. camphora may impact
the EPPO region as the area of suitability increases. Higher
temperatures could cause more rapid growth and biomass
accumulation, resulting in greater impacts to native species.
Therefore, new scores for impact on biodiversity is moderate with
high uncertainty for predicted future climate conditions, based on
changes in temperature and precipitation is:
Impacts on ecosystem sercives and socio-economic impacts will
remain the same.
Other important elements of change, including land-use change and C02 levels are not included in the above scoring.
EWG opinion
28
16. Overall assessment of risk
The overall likelihood of C. camphora entering into the EPPO region is moderate with a low
uncertainty. Within the EPPO region, the species is sold as an ornamental plant and is present
in France, where the species is regarded as casual, growing at the Cap de Ferret, near Bordeaux
and in other European countries (for example, the Netherlands, Italy and Germany) as a planted
species in parks and gardens.
The overall likelihood of C. camphora establishing in the EPPO region is moderate with a
moderate uncertainty - the species is already present in France within the EPPO region. The
overall potential impact of the species is low with a moderate uncertainty.
Pathways for entry:
Plants for planting
Rating of the likelihood of entry for the pathway, plants or seeds
for planting
Low Moderate X High
Rating of uncertainty Low X Moderate High
Rating of the likelihood of establishment in the natural environment in the PRA area Rating of the likelihood of establishment in the natural
environment
Low X
Moderate High
Rating of uncertainty Low Moderate X High
Rating of the likelihood of establishment in the managed environment in the PRA area Rating of the likelihood of establishment in the natural
environment
Low
Moderate X High
Rating of uncertainty Low Moderate X High
Magnitude of spread
Rating of the magnitude of spread Low X
Moderate High
Rating of uncertainty Low Moderate X High
Impact on biodiversity Rating of the magnitude of impact in the current area of
distribution (Biodiversity)
Low
Moderate High X
Rating of uncertainty Low X Moderate High
Impact on ecosystem services Rating of the magnitude of impact in the current area of
distribution (ecosystem services)
Low
Moderate High X
Rating of uncertainty Low X Moderate High
Impact on socio-economics
Rating of the magnitude of impact in the current area of
distribution (ecosystem services)
Low
Moderate X High
Rating of uncertainty Low Moderate X High
29
Will impacts be largely the same as in the current area of distribution? No
Rating for impacts within the EPPO region:
Impact on biodiversity
Rating of the magnitude of impact in the current area of
distribution (Biodiversity) Low X Moderate High ☐
Rating of uncertainty Low ☐ Moderate X High
Negative impact the pest may have on categories of ecosystem services
Rating of the magnitude of impact in the current area of
distribution (ecosystem services)
Low X Moderate High ☐
Rating of uncertainty Low ☐ Moderate X High
Socio-economic impact of the species
Rating of the magnitude of impact in the current area of
distribution (ecosystem services) Low X Moderate High ☐
Rating of uncertainty Low ☐ Moderate X High
30
Stage 3. Pest risk management
17. Phytosanitary measures
The results of this PRA show that Cinnamomum camphora poses a low risk to the
endangered area (Mediterranean and Black Sea biogeographical regions) under current
climatic projections with moderate uncertainty. In the EPPO region Cinnamomum
camphora is recorded (but not invasive) in France, Portugal, and Spain. In France a single
occurrence is recorded, apparently casual.
The Expert Working Group recommends limited phytosanitary measures for this species given
the overall low phytosanitary risk within the endangered area:
• a thorough review of identity and establishment status of Cinnamomum species within
the endangered area,
• Cinnamomum camphora should be monitored for establishment and spread. Casual
occurrences should be eradicated,
• industry correctly labels species in trade, including hybrids,
• the PRA is reviewed every ten years or when significant new information (e.g.
naturalisation in the environment of the endangered area or ecological data) becomes
available.
17.01 Management measures for eradication, containment and control
None recommended under the pest risk management section but see section 12.01 for measures
applied in other regions.
31
18. Uncertainty
Uncertainty should also be considered in the context of species distribution modelling (SDM).
Here records for C. camphora and synonyms were retrieved from GBIF and other online
sources, and were also digitised from occurrences that were either mapped or clearly
georeferenced in published sources. This may mean that the realised climatic niche of C.
camphora is under-characterised. In addition, georeferenced records used in our SDMs were
usually without information on population persistence – if records within the EPPO area, or in
climatically similar areas, are typically of ‘casual’ occurrences, rather than established
populations, it may be that our SDMs over-emphasise the likelihood of establishment in
climatically marginal habitats.
Level of uncertainty of assessment (current/future climate)
Pathway for entry
Plants for planting: Low/Moderate
Likelihood of establishment in natural areas: Moderate/High
Likelihood of establishment in managed areas: Moderate/High
Spread: Moderate/Moderate
Impacts (EPPO region)
Biodiversity: Low/high
Ecosystem services: Moderate/High
Socio-economic: Moderate/High
19. Remarks
None
32
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36
Appendix 1. Projection of climatic suitability for Cinnamomum camphora establishment
Projection of climatic suitability for Cinnamomum camphora establishment
Aim
To project the suitability for potential establishment of Cinnamomum camphora in the EPPO
region, under current and predicted future climatic conditions.
Data for modelling
Climate data were taken from ‘Bioclim’ variables contained within the WorldClim database
(http://www.worldclim.org/), originally at 5 arcminute resolution (0.083 x 0.083 degrees of
longitude/latitude) but bilinearly interpolated to a 0.1 x 0.1 degree grid for use in the model.
Based on the biology of the focal species, the following climate variables were used in the
modelling:
• Mean temperature of the warmest quarter (Bio10 °C) reflecting the growing season thermal
regime. C. camphora is reported to require annual mean temperatures between 14 and 27
°C (Orwa et al., 2011).
• Mean minimum temperature of the coldest month (Bio6 °C) reflecting exposure to frost.
Severe frost is known to damage C. camphora (You et al., 2008).
• Mean annual precipitation (Bio12 ln+1 transformed mm). C. camphora is reported to
require annual preciptatioon between 640 and 4030 mm (Orwa et al., 2011).
• Precipitation of the driest quarter (Bio17 ln + 1 transformed) as a further measure of drought
stress.
To estimate the effect of climate change on the potential distribution, equivalent modelled
future climate conditions for the 2070s under the Representative Concentration Pathway (RCP)
8.5 were also obtained. This assumes an increase in atmospheric CO2 concentrations to
approximately 850 ppm by the 2070s. Climate models suggest this would result in an increase
in global mean temperatures of 3.7 °C by the end of the 21st century. The above variables were
obtained as averages of outputs of eight Global Climate Models (BCC-CSM1-1, CCSM4,
GISS-E2-R, HadGEM2-AO, IPSL-CM5A-LR, MIROC-ESM, MRI-CGCM3, NorESM1-M),
downscaled and calibrated against the WorldClim baseline (see
http://www.worldclim.org/cmip5_5m). RCP8.5 is the most extreme of the RCP scenarios, and
may therefore represent the worst case scenario for reasonably anticipated climate change.
As measures of habitat availability we included:
• Tree cover, which may affect habitability. C. camphora seedlings tolerate some shading,
but require full overhead light once they reach 2-3 m in height (CABI, 2015). Tree cover
was estimated from the MODerate-resolution Imaging Spectroradiometer (MODIS)
satellite continuous tree cover raster product, produced by the Global Land Cover Facility
(DiMiceli et al., 2011). The raw product contains the percentage cover by trees in each
0.002083 x 0.002083 degree grid cell. We aggregated this to the mean cover in our 0.1 x
0.1 degree grid cells and applied a log+1 transformation to improve conformance to
normality.
• Human influence index as many invasive species are known to associate with
anthropogenic disturbance. We used the Global Human Influence Index Dataset of the Last
of the Wild Project (Wildlife Conservation Society - WCS & Center for International Earth
Science Information Network - CIESIN - Columbia University, 2005), which is developed
from nine global data layers covering human population pressure (population density),
37
human land use and infrastructure (built-up areas, nighttime lights, land use/land cover)
and human access (coastlines, roads, railroads, navigable rivers). The index ranges between
0 and 1 and was log+1 transformed for the modelling to improve normality.
As detailed in the main text, C. camphora may have wide edaphic tolerances. Nevertheless, we
included two soil variables, derived from the GIS layers available from SoilGrids
(https://soilgrids.org). Each soil property is provided at depths of 0, 5, 15, 30, 60, 100 and 200
cm as 0.002083 x 0.002083 degree rasters. These were aggregated as the mean soil property
across all depths on the 0.1 x 0.1 degree raster of the model. The soil variables obtained were:
• Soil pH in water as C. camphora may prefer acidic to neutral soils (CABI, 2015)
• Soil sand percentage as C. camphora may be affected by waterlogging.
Species occurrences were obtained from the Global Biodiversity Information Facility
(www.gbif.org), supplemented with data from the literature and the Expert Working Group.
Occurrence records with insufficient spatial precision, potential errors (e.g. a record
georeferenced in Saudi Arabia that was labelled as originating in China) or that were outside
of the coverage of the predictor layers (e.g. small island or coastal occurrences) were excluded.
Six records from planted gardens in Sweden, Ireland, Germany and Netherlands were also
excluded from the modelling. The remaining records were gridded at a 0.1 x 0.1 degree
resolution (Figure 1).
In total, there were 1234 grid cells with recorded occurrence of C. camphora available for the
modelling (Figure 1).
Figure 1. Occurrence records obtained for Cinnamomum camphora used in the model, after
exclusion of planted records from the non-native range.
Species distribution model
A presence-background (presence-only) ensemble modelling strategy was employed using the
BIOMOD2 R package v3.3-7 (Thuiller et al., 2014, Thuiller et al., 2009). These models
contrast the environment at the species’ occurrence locations against a random sample of the
global background environmental conditions (often termed ‘pseudo-absences’) in order to
characterise and project suitability for occurrence. This approach has been developed for
distributions that are in equilibrium with the environment. Because invasive species’
distributions are not at equilibrium and subject to dispersal constraints at a global scale, we
took care to minimise the inclusion of locations suitable for the species but where it has not
been able to disperse to. Therefore the background sampling region included:
38
• The native continent of C. camphora, in which the species is likely to have had sufficient
time to cross all biogeographical barriers. For the model we used the whole of Asia, even
though the species has been reported as introduced to some parts of Asia; AND
• A relatively small 50 km buffer around all non-native occurrences, encompassing regions
likely to have had high propagule pressure for introduction by humans and/or dispersal of
the species; AND
• Regions where we have an a priori expectation of high unsuitability for the species (see
Fig. 2). The following rules were applied to define the region expected to be highly
unsuitable for C. camphora:
o Mean minimum temperature of the coldest month (Bio6) < -10 °C. C. camphora
experiences frost damage below -10 C (You et al., 2008) and the coldest location
with a presence in our dataset has Bio6 = -9.9 °C.
o Mean temperature of the warmest quarter (Bio10) < 15 °C, which is consistent with
reported low tolerances for the mean annual temperature (Orwa et al., 2011). Only
one occurrence is in a colder location than this.
o Annual precipitation (Bio12) < 640 mm, which is consistent with reported
minimum moisture requirements (Orwa et al., 2011). In our database 29
occurrences (2.4%) are in drier locations than this. Since this is a small percentage
of the records it was reasonable to assume that locations this dry are generally of
low suitability.
Within this sampling region there will be substantial spatial biases in recording effort, which
may interfere with the characterisation of habitat suitability. Specifically, areas with a large
amount of recording effort will appear more suitable than those without much recording,
regardless of the underlying suitability for occurrence. Therefore, a measure of vascular plant
recording effort was made by querying the Global Biodiversity Information Facility application
programming interface (API) for the number of phylum Tracheophyta records in each 0.1 x 0.1
degree grid cell. The sampling of background grid cells was then weighted in proportion to the
Tracheophyte recording density. Assuming Tracheophyte recording density is proportional to
recording effort for the focal species, this is an appropriate null model for the species’
occurrence.
To sample as much of the background environment as possible, without overloading the models
with too many pseudo-absences, five background samples of 10,000 randomly chosen grid
cells were obtained (Figure 2).
39
Figure 2. Randomly selected background grid cells used in the modelling of Cinnamomum
camphora, mapped as red points. Points are sampled from the native continent (Asia), a small
buffer around non-native occurrences and from areas expected to be highly unsuitable for the
species (grey background region), and weighted by a proxy for plant recording effort.
Each dataset (i.e. combination of the presences and the individual background samples) was
randomly split into 80% for model training and 20% for model evaluation. With each training
dataset, ten statistical algorithms were fitted with the default BIOMOD2 settings, except where
specified below:
• Generalised linear model (GLM)
• Generalised boosting model (GBM)
• Generalised additive model (GAM) with a maximum of four degrees of freedom per
smoothing spline.
• Classification tree algorithm (CTA)
• Artificial neural network (ANN)
• Flexible discriminant analysis (FDA)
• Multivariate adaptive regression splines (MARS)
• Random forest (RF)
• MaxEnt
• Maximum entropy multinomial logistic regression (MEMLR)
Since the background sample was much larger than the number of occurrences, prevalence
fitting weights were applied to give equal overall importance to the occurrences and the
background. Variable importances were assessed and variable response functions were
produced using BIOMOD2’s default procedure. Model predictive performance was assessed
by calculating the Area Under the Receiver-Operator Curve (AUC) for model predictions on
the evaluation data, that were reserved from model fitting. AUC can be interpreted as the
probability that a randomly selected presence has a higher model-predicted suitability than a
randomly selected absence. This information was used to combine the predictions of the
different algorithms to produce ensemble projections of the model. For this, the three
algorithms with the lowest AUC were first rejected and then predictions of the remaining seven
algorithms were averaged, weighted by their AUC. Ensemble projections were made for each
dataset and then averaged to give an overall suitability.
40
Results
The ensemble of the seven statistical algorithms suggested that suitability for C. camphora was
most strongly determined by the mean temperature of the warmest quarter, soil pH, annual
precipitation and the minimum temperature of the coldest month (Table 1). From Fig. 3, the
ensemble model estimated the optimum conditions for occurrence at approximately:
• Mean temperature of the warmest quarter = 27.6 °C (>50% suitability with bio10 > 17.7
°C)
• Low soil pH (>50% suitability with pH < 7.5)
• Annual precipitation = 1521 mm
• Minimum temperature of the coldest month = 5.5 °C
These optima and ranges of high suitability described above are conditional on the other
predictors being at their median value in the data used in model fitting.
The model also characterised slight habitat preferences for wet driest quarters, high human
influence, low tree cover and sandy soils (Fig. 3).
There was substantial variation among modelling algorithms in the partial response plots,
especially for precipitation (Fig. 3). In part this will reflect their different treatment of
interactions among variables. Since partial plots are made with other variables held at their
median, there may be values of a particular variable at which this does not provide a realistic
combination of variables to predict from. It also demonstrates the value of an ensemble
modelling approach in averaging out the uncertainty between algorithms.
Global projection of the model in current climatic conditions (Fig. 4) indicates that the native
and known invaded records (Fig. 1) generally fell within regions predicted to have high
suitability. In Europe and the Mediterranean region, there are no areas predicted to have very
high suitability for invasion by C. camphora in the current climate (Fig. 5). However, marginal
suitability is predicted around much of the coastline of southern Europe, from southwest
France, round the Atlantic coast of Iberia and around the northern shores of the Mediterranean
to the Middle East. Areas of marginal suitability are also predicted in western Iberia and the
Azores.
By the 2070s, under climate change scenario RCP8.5, projected suitability for C. camphora in
Europe increases substantially (Fig. 6). Much of Mediterranean and western Europe is
predicted to become suitable for the species.
41
Table 1. Summary of the cross-validation predictive performance (AUC) and variable importances of the fitted model algorithms and the ensemble
(AUC-weighted average of the best performing seven algorithms). Results are the average from models fitted to five different background samples
of the data.
Algorithm Predictive
AUC
Variable importance
Minimum
temperature
of coldest
month
Mean
temperature
of warmest
quarter
Annual
precipitation
Precipitation of
driest quarter
Tree
cover
Human
influence Soil pH
Soil sand
content
GBM 0.9710 4.8% 49.6% 43.7% 0.7% 0.3% 0.7% 0.3% 0.0%
ANN 0.9690 10.8% 44.0% 6.0% 7.0% 2.6% 4.7% 24.7% 0.3%
GAM 0.9682 7.2% 55.1% 9.8% 0.8% 1.5% 3.3% 22.3% 0.1%
MARS 0.9660 7.7% 58.6% 16.0% 0.0% 0.6% 4.0% 13.1% 0.0%
GLM 0.9658 10.4% 50.9% 3.9% 0.4% 1.1% 3.4% 29.9% 0.1%
RF 0.9582 10.3% 44.8% 20.9% 12.9% 1.9% 2.4% 4.4% 2.3%
MEMLR 0.9514 0.1% 55.4% 0.2% 1.0% 2.5% 3.9% 36.7% 0.2%
FDA 0.9494 7.8% 69.2% 3.5% 4.3% 2.7% 1.5% 10.3% 0.6%
CTA 0.9328 6.6% 43.1% 48.4% 0.0% 1.4% 0.5% 0.0% 0.0%
MaxEnt 0.9262 8.6% 35.0% 22.1% 5.1% 5.2% 3.2% 9.3% 11.6%
Ensemble 0.9690 7.4% 51.2% 14.4% 3.2% 1.5% 3.2% 18.7% 0.4%
Figure 3. Partial response plots from the fitted models, ordered from most to least important. Thin
coloured lines show responses from the seven algorithms, while the thick black line is their
ensemble. In each plot, other model variables are held at their median value in the training data.
Some of the divergence among algorithms is because of their different treatment of interactions
among variables.
43
Figure 4. Projected global suitability for Cinnamomum camphora establishment in the current
climate. For visualisation, the projection has been aggregated to a 0.5 x 0.5 degree resolution, by
taking the maximum suitability of constituent higher resolution grid cells. Values > 0.5 may be
suitable for the species. The white areas have climatic conditions outside the range of the training
data so were excluded from the projection.
44
Figure 5. Projected current suitability for Cinnamomum camphora establishment in Europe and
the Mediterranean region. For visualisation, the projected suitability has been smoothed with a
Gaussian filter with standard deviation of 0.1 degrees longitude/latitude. The white areas have
climatic conditions outside the range of the training data so were excluded from the projection.
Figure 6. Projected suitability for Cinnamomum camphora establishment in Europe and the
Mediterranean region in the 2070s under climate change scenario RCP8.5, equivalent to Fig. 5.
45
Caveats to the modelling
To remove spatial recording biases, the selection of the background sample was weighted by the
density of Tracheophyte records on the Global Biodiversity Information Facility (GBIF). While
this is preferable to not accounting for recording bias at all, a number of factors mean this may not
be the perfect null model for species occurrence:
• The GBIF API query used to did not appear to give completely accurate results. For example,
in a small number of cases, GBIF indicated no Tracheophyte records in grid cells in which it
also yielded records of the focal species.
• We located additional data sources to GBIF, which may have been from regions without GBIF
records.
Some variables potentially affecting the distribution of the species, such as soil nutrients, were not
included directly in the model.
The climate change scenario used is the most extreme of the four RCPs. However, it is also the
most consistent with recent emissions trends and could be seen as worst case scenario for
informing risk assessment.
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Appendix 2 Biogeographical regions in Europe
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Appendix 3. Relevant illustrative pictures (for information)
Figure 1. Cinnamomum camphora (Forest and Kim Starr, Starr Environmental, Bugwood.org)
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Figure 2. Cinnamomum camphora (Forest and Kim Starr, Starr Environmental, Bugwood.org)
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Figure 3. Cinnamomum camphora (Forest and Kim Starr, Starr Environmental, Bugwood.org)
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Figure 4. Cinnamomum camphora (Forest and Kim Starr, Starr Environmental, Bugwood.org)
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Figure 5. Cinnamomum camphora (Forest and Kim Starr, Starr Environmental, Bugwood.org)
Appendix 4. Distribution maps of Cinnamomum camphora
Figure 1. World distribution (GBIF data)
Figure 2. Distribution map of Cinnamomum camphora in North America (GBIF data)
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Figure 3. Distribution map of Cinnamomum camphora in Europe (GBIF data)
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Figure 4. Distribution map of Cinnamomum camphora in Asia (GBIF data)
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Figure 5. Distribution map of Cinnamomum camphora in Australia (GBIF data)
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Figure 6. Distribution map of Cinnamomum camphora in South America (GBIF data)
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Figure 7. Distribution map of Cinnamomum camphora in Africa (GBIF data)
